Dear Carolina,

The easiest method to acquire the MODIS PAR and euphotic zone depth data that you desire is to use MGET’s tools that are designed specifically for the NASA OceanColor data. These tools download the HDFs and convert them for you and are much faster than downloading them manually and using the Convert SDS in HDF to ArcGIS Raster tool. These new tools have been available for a while but I have not created examples of them yet. (I am sorry about that!)

To use the new tools, I recommend that you first shutdown your ArcGIS programs, uninstall your existing copy of MGET (from Control Panel à Add/Remove Programs on Windows XP, or Control Panel à Programs And Features on Windows Vista and 7), and then download and install the latest one from http://code.nicholas.duke.edu/projects/mget/.

Then, to download the data:

1.    Start ArcGIS and go to Marine Geospatial Ecology Tools à Data Products à NASA GSFC OceanColor Group.

2.    Open the tool called Create Rasters for NASA OceanColor L3 SMI Product.

3.    Choose the Sensor, Temporal Resolution, and Spatial Resolution you want.

4.    In the Level 3 SMI Product Code box, you must type in the code corresponding to the product you want. The documentation for this parameter lists many of the codes. For PAR, the code is PAR_par and for Lee’s euphotic zone depth the code is KDLEE_Zeu_lee

5.    You may also want to specify a Start Date and End Date under the Spatialtemporal Extent options. If you do not specify these, the tool will download all available files. For MODIS Aqua, those will be from 2002 until 2012.

6.    Now run the tool.

Good luck,

Jason